Changes over 26 Years in the Avifauna of the Bogotá Region, Colombia: Has Climate Change Become Important?

High Neotropical mountains are among the most threatened ecosystems by climate change and this problem could be accentuated in cities where temperatures are higher. However, there are few data of long-term avifaunal changes in Neotropical cities, and the potential impact of climate change has yet to be addressed. Using data from 26 years of Audubon's Christmas Bird Counts (CBCs) in the Bogotá area (ca. 2,600–3,100 m in Colombia's eastern Andes), we analyze long-term changes of the avifauna using linear regressions corrected for species' habitat preferences and compared urban and rural sites. For the CBC we followed the National Audubon Society's methodology in which birds are counted over a 24-h period within a fixed circle 24 km in diameter. We recorded 235 species in the Bogotá circle with an average of 122 spp/year, including 46 boreal migrants, three endemic species, and four endemic subspecies, two globally and four locally threatened species. Species richness was higher in rural than in urban areas and most species were associated with native forest and scrub and wetlands. Among the species that were analyzed for changes in time 31% increased, 20% decreased, and 49% did not change. Strong fluctuations or changes in abundance were more frequent in urban than rural environments. Many of the species that increased or became established during the CBC interval came from lower elevations or the warmer, drier parts of the region beyond the count circle. By contrast, the lower elevational limits moved to higher elevations in several species that decreased. Climate change with its related effects represented the factor associated with the most changes in abundance. Other potential causes were direct human actions, mostly associated with urbanization, and “natural” successional changes in vegetation; predation by feral dogs and cowbird parasitism also affected several species negatively. Observations indicate that these factors will continue into the future, and the effects of climate change and urbanization in particular will probably intensify. The Bogotá CBC has provided much valuable information for Neotropical urban ornithology and its practice should be encouraged in other Latin American cities and should definitely continue in Bogotá for many years to come

Cambios en la avifauna de un relicto de bosque en la franja periurbana de Bogotá a lo largo de catorce años

A lo largo de varios siglos, la vegetación nativa de la parte plana de la Sabana de Bogotá ha sido casi completamente sustituida por cultivos, potreros y urbanizaciones. El último relicto de esta vegetación es un pequeño bosque (ca 10 ha), ubicado en la Hacienda Las Mercedes en el borde norte de la ciudad de Bogotá. El tamaño reducido y aislamiento del bosque, agravado por el crecimiento descontrolado de vegetación invasiva (lianas y zarzamora silvestre) ha generado la pérdida de muchas especies. Sin embargo, en los últimos años el bosque ha sido objeto de acciones de rehabilitación y actualmente la zona está inmersa en una reserva en donde se prevén programas de restauración más amplios. Con el objetivo de evaluar los cambios en la comunidad de aves para estimar los efectos de las acciones de restauración, se registró la avifauna presente en 2001-2002 y en el 2014, mediante registros visuales y auditivos en puntos fijos en el bosque. En el primer censo se encontraron 27 especies de bosque y en el segundo 30, y las abundancias relativas de por lo menos la tercera parte de ellas también aumentó en los 13 años, indicando un resultado positivo en la recuperación del bosque. Los resultados resaltan la capacidad de recuperación de los ecosistemas degradados y la importancia de continuar con las acciones de restauración en el área de reserva.The native vegetation of the Sabana de Bogota’s flat area has been replaced by agricultural lands, pastures and urbanizations over the years. The last relict of this native vegetation is a small forest (ca 10 ha) at Hacienda Las Mercedes, in the northern border of Bogota. The forest’s small size and isolation from other areas of natural vegetation have resulted in the loss of many species. The problem was exacerbated by uncontrolled growth of invasive vegetation (vines and wild blackberry). However, in recent years restorative action including control of these vegetation has been undertaken and the forest is now immerse in a natural reserve where more restorative actions are being planned. Using point count stations the authors recorded all the birds seen and heard in 2001-2002 and in 2014 in order to evaluate the changes in the bird community and estimate the effects of the restorative actions. We recorded 27 forest species in the first census and 30 in the second. The relative abundance of at least 1/3 of the species also increased indicating a positive result in the forest restoration. The results highlight the capacity of degraded ecosystems to recover and the importance of continuing the restorative actions in the reserve area

Lista de chequeo de las aves de Colombia: Una síntesis del estado del conocimiento desde Hilty & Brown

The taxonomy and knowledge of the distribution of Colombian avifauna has undergone great changes since the publication of “A Guide to the Birds of Colombia” by Hilty & Brown (1986) to the extent that we are unaware of how many and which species inhabit the Colombian territory. Here, we present a checklist of the birds of Colombia updated to August 2017 with a review of 340 references dealing with the distribution of Colombian birds. In sum, we report 1909 species for continental and insular Colombia, 216 of which have been added mainly since 1986. Although there are new data on distribution from 66% of the Colombian avifauna, most publications (87%) and new records (53%) are concentrated to the west of the Eastern cordillera (trans-Andean region). Based on the data we identify those regions of the country with knowledge gaps, which deserve more interest from researchers. Moreover, we encourage the ornithological community to publish their unpublished data and to improve the evidence supporting future new records for the country.La taxonomía y conocimiento de la distribución de la avifauna colombiana ha sufrido grandes cambios desde la publicación de “A Guide to the Birds of Colombia” por Hilty & Brown (1986), a tal punto que hoy no se sabe con precisión cuántas y cuáles especies de aves existen en el territorio colombiano. Presentamos la lista de chequeo de la avifauna de Colombia a agosto de 2017 con base en la revisión de 340 referencias relacionadas con la distribución de la avifauna colombiana. En total, reportamos 1909 especies de aves para el territorio continental e insular del país, de las cuales 216 han sido adicionadas principalmente a partir de 1986. Aunque existe información novedosa sobre distribución para cerca del 66% de la avifauna colombiana, la mayoría de las publicaciones (87%) y registros (53%) se concentran al occidente de la cordillera Oriental (región transandina). Con base en esta información identificamos aquellas áreas del país con vacíos de conocimiento que ameritan mayor interés por parte de los investigadores. Además, estimulamos a la comunidad ornitológica a publicar la información inédita represada, al igual que mejorar la evidencia que soporta los registros novedosos para el país

Diagnóstico para una propuesta de monitoreo comunitario en el Macizo del Cerro de la Muerte (Costa Rica)

Different human activities modify the natural processes of the environment; therefore, it is necessary to record changes, possible causes and design strategies to mitigate their impact. To follow up on the changes, data is continuously recorded through participatory monitoring, which is very effective for the conservation of biological resources, since the community and people involved are the ones who best know their territory and the organisms living there. The main purpose of this study was to carry out the first stage of the design of a participatory monitoring initiative with the communities bordering the “Cerro Vueltas” Biological Reserve, located in “Macizo de la Muerte”, in the provinces of Cartago and San José, in the Talamanca mountain range, Costa Rica. Semi-structured interviews were conducted by means of a survey with 18 questions, 12 of which being semi-open-ended and six closed-ended. The results of the surveys show that tourism in this area is one of the main economic activities for the community. In addition, it is acknowledged that a series of threats related to climate change, land use change and mainly due to the expansion of coffee growing areas and purchase of land by foreigners are impacting their environment and tourism as an economic activity.Diferentes actividades humanas modifican los procesos naturales del entorno, por lo que es necesario registrar los cambios, las posibles causas y diseñar estrategias para mitigar su influencia. Para hacer el seguimiento efectivo de los cambios se registran continuamente los datos a través del monitoreo participativo, efectivo para la conservación de recursos biológicos, ya que la comunidad y las personas interesadas son las que mejor conocen su territorio y los organismos que lo habitan. El objetivo principal del estudio consistió en realizar la primera etapa del diseño de un monitoreo participativo con las comunidades aledañas a la Reserva Biológica Cerro Vueltas, ubicadas en el área del Macizo del Cerro de la Muerte, las provincias de Cartago y San José, en la Cordillera de Talamanca, Costa Rica. Se realizaron entrevistas semiestructuradas empleando una encuesta con 18 preguntas, de las cuales 12 fueron semiabiertas y seis cerradas. Los resultados de las encuestas evidencian que el turismo en la zona es una de las actividades económicas principales para la comunidad. Además, se reconocen una serie de amenazas relacionadas con el cambio climático, por ejemplo, el cambio de uso de suelo, principalmente por la expansión de las áreas de cultivo de café, y la compra de predios por extranjeros. Amenazas que impactan tanto su entorno como al turismo como actividad económica

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

Factores ambientales relacionados con la presencia y abundancia de las aves de los humedales de la Sabana de Bogotá

Con el uso de sistemas de información geográfica e imágenes remotas de alta resolución y observaciones de aves en 19 humedales de la Sabana de Bogotá, evalué la influencia de las características locales de hábitat y las de paisaje sobre la riqueza y composición de las comunidades aviares del área y sobre la densidad y abundancia de siete especies particulares. Los humedales estuvieron cubiertos por una alta proporción de vegetación relacionada con la eutroficación (principalmente en humedales urbanos) o por espejos de agua predominantes con poca vegetación emergente (humedales rurales). Tanto la riqueza general de la avifauna como la abundancia de las especies estudiadas en detalle se relacionaron con el área del humedal; mientras que las densidades se relacionaron con factores particulares en cada especie. La avifauna acuática de la Sabana de Bogotá permanece gracias a la diversidad de coberturas y características de los humedales remanentes lo que requiere una estrategia regional de conservación. / Abstract. Using GIS and high definition remote images and bird observations in 19 wetlands, I evaluated the influence of landscape and local habitat characteristics on the richness and composition of bird communities in the area and in the density and abundance of seven particular species. Wetlands either had a high proportion of vegetation cover due to eutrophication (mostly in urban landscapes) or were mostly open water with less emergent vegetation (mostly rural landscapes). Both bird richness and abundance were related to wetland size while densities were related to varied factors particular to each species. Conservation of wetland birds in the Sabana de Bogotá is possible due to the differences in both vegetation covers and landscape characteristics in the remaining wetlands. This situation calls for a regional aproximation to conservation.Doctorad

Biología reproductiva de porphyriops melanops bogotensis (Gruiformes, rallidae) subespecie endémica y amenazada del norte de los andes

The Rallidae is a widely distributed family in the planet, with a high proportion of endangered species and limited information on reproductive biology. Porphyriops melanops bogotensis is an endangered and isolated endemic Colombian subspecies and no detailed information about its breeding biology and nestling development. We describe the breeding biology of P. m. bogotensis and the development of the nestlings, thus providing novel information that may help its conservation. The study was done in the Bogotá area highland plateau between 2016 and 2019. We surveyed the area weekly in search of nests for description and monitoring. We artificially incubated fourteen eggs; these chicks were raised in captivity until completely developed while measuring growth and taking notes on color changes. The birds nested all year long; clutch size varied between three and six eggs, with an incubation period of 18-20 days. The rails reached their definite size by day 55, with significant differences between sexes. The beak acquired the final color by day 75, while adult eye and plumage color were reached between 150 and 165 days after hatching. In general terms reproductive behavior and development of P. m. bogotensis are like what is known for other members of the Rallidae. The detailed description of coloration change of the subspecies during its development allows precise age determination of individuals in the wild

Inventario de las aves de un bosque altoandino: comparación de dos métodos

La captura con redes de niebla ha sido utilizada o propuesta como método único para realizar inventarios de aves en varios bosques neotropicales, pero pocas veces ha sido evaluado en este medio en relación a otros métodos como el de las observaciones visuales y auditivas. Este estudio compara la efectividad y eficiencia de estos dos métodos en la elaboración de la lista de las especies de aves de una parcela de 15 ha de bosque altoandino y subpáramo en la Cordillera Oriental de Colombia. Durante diez meses hicimos once visitas de 4-6 días al área; observamos y pusimos redes a lo largo de ca. 3 km de senderos. Registramos 102 especies durante el estudio, 101 mediante las observaciones y 50 con capturas; 52 especies fueron observadas pero no capturadas y solamente una fue capturada sin ser observada. Las observaciones fueron más eficientes en la acumulación de especies, con un promedio de 68.4 especies por visita, vs. 17.1 capturadas. Una visita bastó para anotar 50% del total de las especies observadas y seis para el 90%; las cifras correspondientes para las capturas fueron cuatro y nueve visitas. La muestra de especies capturadas fue sesgada a favor de aves pequeñas « 50 g); ciertos grupos dietéticos y gremios de forrajeo estuvieron sobrerrepresentados, otros subrepresentados o hasta ausentes. Concluimos que las observaciones visuales y auditivas permiten llevar a cabo un inventario más completo y representativo en menos tiempo. Las redes son un suplemento útil pero no sustituyen tales observaciones y alcanzan su mayor utilidad en la toma de otros tipos de datos.Capturing birds with mist-nets has been the sole method used or proposed for making species inventories of several Neotropical forests, but this method has rarely been evaluated relative to the use of visual and auditory observations in these forests. This study compares the effectiveness and efficiency of these two methods in the elaboration of the list of bird species on a 15 ha study plot of forest and subparamo vegetation in the Eastern Andes of Colombia. Over ten months we made 11 visits of 4-6 days each, observing and running nets along ca. 3 km of study trails. Of 102 total species recorded, 101 were observed and 50 captured; 52 were observed but not captured vs. only one that was only recorded with the nets. The observations were more efficient in accumulating species, with a mean of 68.4 per visit vs. 17.1 species captured. More than half of the species observed had been recorded after a single visit, and over 90% in six visits; the corresponding figures for mist-net captures were four and nine visits. Compared with the totallist, the mist net sample was biased towards small species « 50 g); some diet groups or foraging guilds were over- or underrepresented in this sample. We conclude that visual and auditory observations are more effective and efficient for making inventories of birds in these forests. Mist nets are a useful supplement to these observations, but not a substitute; their greatest utility lies in obtaining other sorts of data

New and noteworthy records of birds from the middle Magdalena valley of Colombia

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Changes in the avifauna in a high Andean cloud forest in Colombia over a 24‐year period

Los ecosistemas altoandinos están entre los mas amenazados por cambio climático. Los modelos computacionales existentes indican que un alto porcentaje de especies sobrellevar a riesgo severo de extinción y que las comunidades aviares sufrirán disturbios y empobrecimiento. Estudios en otros países andinos soportan de alguna manera estas predicciones pero no hay datos apropiados en Colombia para corroborarlos. En 1991– 1992 habíamos hecho un inventario detallado de la avifauna de un bosque de niebla con información sobre la composición y abundancia de las especies, la estructura trófica y los gremios de alimentación. Aquí presentamos los resultados de la repetición del estudio anterior 24 años más tarde, para detectar cambios en la avifauna y establecer posibles causas. Durante 2015–2016 visitamos el _área cada dos meses repitiendo los mismos métodos previos: detecciones visuales y auditivas para estimar las abundancias de las especies, complementadas con capturas con redes de niebla. En general no se dieron cambios notables en la riqueza ni composición de la comunidad ni en la abundancia general de las aves, por lo tanto a este nivel los cambios aparentemente están ocurriendo más lentamente que lo predicho. Sin embargo, se dieron cambios en las abundancias del 30% de las especies. De acuerdo con las predicciones de los modelos de cambio climático, nueve o diez especies aparentemente han desplazado sus límites de elevación inferiores o superiores hacia arriba. No obstante, la mayoría de cambios en abundancia parecen reflejar cambios en la vegetación del _área de estudio debido a cambios sucesionales en los hábitats de bosque y subpáramo, al gran número de caídas recientes de _arboles grandes del dosel con cargas pesadas de epífitas y sus consecuencias en la vegetación del sotobosque. Aunque los cambios relacionados al cambio climático parecen estar ocurriendo más lentamente que lo predicho por algunos modelos teóricos, concluimos que es importante tenerlos en cuenta en estudios de aquí en adelante. Sin embargo, estudios en un solo sitio como esto tienen limitaciones para la documentación de cambios en los límites elevacionales. Para esto, estudios a largo plazo sobre un ámbito amplio de elevaciones son mas concluyentes y recomendamos el establecimiento de un programa de monitoreo de este tipo en Colombia. Los datos en un programa de ese tipo podrían ser importantes para el diseño de medidas para mitigar los efectos del cambio climático y la conservación de la biodiversidad.The upper altitude ecosystems of the Andes are among the most threatened by climate change. Computer models suggest that a large percentage of species in these ecosystems will be at risk of extinction and that avian communities will suffer disruption and impoverishment. Studies in other Andean countries lend some support to these predictions, but there are no quantitative data from Colombia appropriate to test these models. In 1991–1992, we conducted a bird survey in a high Andean cloud forest to gather information about the species present and their abundance. We attempted to replicate this earlier study 24 yr later to detect any changes in the avifauna and determine possible causes for those changes. From June 2015 to May 2016, we made bimonthly trips to the study site and identified all birds detected either visually or by voice along a number of trails. We supplemented our observational data by also capturing birds in mist-nets. Community species richness and composition as well as the overall abundance of birds changed little from 1991–1992 to 2015–2016, but nearly 30% of bird species changed in abundance. Changes in the presence or abundance of nine or 10 species reflected upward shifts in elevational limits potentially due to climate change. However, most changes in abundance appeared to reflect changes in the vegetation of the study area due to successional changes in forest and subparamo habitats and a large number of relatively recent treefalls of old canopy trees with heavy epiphyte loads and subsequent changes in the understory vegetation. Our results suggest that the effects of climate change on the avifauna in our study area at a high-altitude site in Colombia are apparently occurring more slowly than predicted by recent computer models, although we conclude that the possible effects of climate change should definitely be considered in future studies. However, single-site studies such as ours have limitations in documenting elevation shifts; the most conclusive and quantitative evidence for elevational shifts comes from long-term studies conducted over a wide range of elevations. As such, we recommend establishment of such a monitoring program in Colombia because data obtained from such a program might be important in designing measures to mitigate the effects of climate change and conserve biodiversity. © 2017 Association of Field Ornithologist